Anesthesiology and Critical Care In an Age of Mass Casualty Events

It is Monday morning. You are setting up your operating room (OR) for your regularly scheduled laparoscopic cholecystectomy or hernia repair. You are number 10 on the release list that day, so chances are good that you will be released before the second case finishes. You start to think, “Should I take my lunch break at 11 AM, just in case I get released early?” Suddenly, the building shudders.

You think nothing of it and continue setting up your room: machine check, airway equipment, monitors, and induction drugs. It is not until you run into the nursing coordinator that you find out there’s been a large explosion at the local shopping mall 1.5 miles away. At that point you see the anesthesiologist in charge for the day, and she asks you to go down to the emergency department (ED) to find out what is happening.

Triage station at the Pentagon after the impact of American Airlines Flight 77 during the September 11, 2001, attacks.

Once you arrive in the ED, you see the first victims rolling in as 3 ambulances pull up simultaneously to the entrance. It is chaos. You are pushed out of the way by nurses scrambling to get supplies, and the trauma team begins working on the first patient to arrive. You hear a paramedic state he thinks there were chemicals involved in the explosion because his skin and eyes are burning. What do you do? Where do you start? Do you return to the OR and wait to be called to start a case?

Unfortunately, terrorism and natural disasters are nothing new to our world. On Friday, November 13, 2015, terrorists detonated devices nearly simultaneously in different parts of Paris, France, while another team of terrorists conducted shootings at 4 different locations throughout the city.¹As the SAMU (Service d’Aide Médicale Urgente) and emergency response system (known as the Red Plan and White Plan in France) were activated, an anesthesiologist on staff at Pitié-Salpêtrière Hospital in Paris noted that staff began to flood the hospital. The hospital normally runs 2 ORs on a given day. However, on that day, given the number of penetrating injuries requiring emergent and urgent surgery, they flexed to open 10 ORs. According to one of the trauma surgeons there on that day, by the time he arrived at the hospital, the on-call anesthesiologists and intensivists were being assisted by several of their colleagues who had already come to the hospital from home.

According to the anesthesiologist, the factors that contributed to their success that day were preparation in the months preceding the attacks, excellent cooperation among all caregivers, and good organization. Before patients even arrived at the hospital, the anesthesiologists, intensivists, and surgeons cleared the PACUs and converted them into expanded ICU space to accommodate all postsurgical patients. The ED set up an initial triage station at the entrance of the hospital that funneled trauma and life-threatening injuries to the shock trauma bay and more stable injuries and shock states to the ED. The ED secondary triage team then took a second look at all patients sent to them to ensure no injuries were missed. The critical patients were each taken care of in the shock trauma bay and eventually to the OR and expanded ICU by a trauma team that included an anesthesiologist, a surgeon, a fellow, and a nurse who decided collectively what additional workup was needed and who needed to go to the OR emergently. The trauma teams operated all night on the first night and through the day and night of the next day. By the third day after the attacks, the hospital resumed normal operations.¹

According to one of the trauma surgeons at Pitié-Salpêtrière Hospital:

“Professionalism was present at every level. While the operating room is often described as a difficult place—where the human factor is crucial—during this ‘stress test’ difficulties vanished, working together appeared fluid and somehow harmonious. Trust and communication between different specialties and jobs were apparent. The common goal was so clear that no stakeholder tried to impose an individual view.”¹

As the French experience exemplifies, we as a profession are only as prepared and as good as we push ourselves to be. With US surveys of anesthesiologists’ attitudes toward emergency preparedness showing that only one-third of residency programs still provide disaster education and half have eliminated this training, we must reassess the direction we wish our field to take.²The following may serve to rekindle the spirit of trailblazing, innovation, and dedication that has molded anesthesiology in the past—from the development of the world’s first ICUs to taking the lead in patient safety and quality improvement measures—all to better serve our patients.

Disaster Management Basics

Preparation

Preparation for disasters occurs months and years before a disaster. It involves not only hospital-wide but city-, state-, and nationwide planning. Government at the federal and state levels has established systems such as the National Incident Management System (NIMS), which falls under the Federal Emergency Management Agency (FEMA). NIMS was established to ensure a standardized method in which the federal government and state and local agencies can work together efficiently in the event of a crisis. Within this paradigm, the National Response Framework functions as a guide to ensure mechanisms are in place for the federal government to provide aid to state and local jurisdictions (Table 1).³ However, it is important to realize that these systems are in place to facilitate and assist. It is the local communities that retain command and control over any relief and response operations within their jurisdictions.⁴

Disaster planning requires considerable effort at the local level. The disaster plan must be comprehensive in its breadth and detailed enough in its depth that it provides true guidance to each entity involved in the response. However, there must also be room for flexibility so that local leaders and on-site personnel can work around unforeseen obstacles.⁴ This scope of planning requires commitment from community leaders and municipal governments to local hospital, police, fire, and utility administrators. Once the commitment has been made, the challenge is to correctly identify which problems a disaster, whether related to terrorism or naturally occurring, poses for the community. To effectively do this, planners must critically analyze prior disasters and the responses to events and identify shortcomings.⁵

With regard to medical response during a disaster, planners must remember that the delivery of medical care during a disaster shifts from focusing on a few individual patients to the injured population at large. In a true mass casualty event (MCE), medical personnel, supplies, and resources must be used in a manner that allows for care to as many patients as possible.⁴

Just as FEMA has established NIMS during a disaster, hospitals and communities also will have incident command systems (ICS) in place. The medical ICS or hospital incident command system (HICS) will be located in community hospitals and delineates who is in command during an emergency. More importantly, however, it establishes lines of communication between HICS and the community ICS. Additionally, HICS should have common goals, streamlined action plans that are simple to follow, modular organization, use of common terminology, a common mode of communication, and resource management integrated into the system.⁴

At the top of HICS is one commander who establishes priorities during each phase of the disaster response. Selected section chiefs will then serve in 1 of the 4 roles reporting to the HICS commander (Figure 1). As part of the hospital emergency action plan, each section chief reporting to the HICS commander should have action sheets, which specify the roles of each person reporting to the HICS commander.⁴ Ideally, the supervisor-to-worker ratio within HICS is 1:5.⁴ The purpose of establishing these structural elements within a hospital and community are to streamline operations and communications during a disaster. Once a hospital establishes an emergency action plan, conducting regular drills with the community ICS helps to identify weaknesses in the system, cement individual roles during a disaster, and strengthen the sense of teamwork within the hospital and community. In the military, mass casualty drills are commonplace during peacetime. The drills aboard ships in the US Navy will often incorporate all departments, with department heads organizing and leading their department’s response (Figures 2 and 3). These drills are vital to preparation.

Figure 1. Personnel reporting to the medical incident commander.

• comprehensive planning
• thorough emergency operations plans
• defined response capability
• ongoing surveillance, reporting, and agent identification

The Anesthesiologists’ Role

The anesthesiologists’ role in disaster management begins with a thorough understanding of the hospital’s disaster and emergency operations plan and protocols, as detailed above. Many anesthesiologists do not know their hospital’s contingency plans, who the HICS commander is, or the relationship between the community ICS and HICS.

In many US hospitals, anesthesiologists are not included in hospital disaster drills or emergency management plans.⁶ In one local hospital, anesthesiologists in the main OR were notified just a few hours before a community-wide disaster drill commenced. They were given no direction or formalized plan. Anesthesiologists, as resuscitative specialists, are uniquely suited to provide care at a multitude of locations. Marginalizing anesthesiologists from hospital and community disaster planning wastes a resuscitative physician capable of airway management, management of shock states, transfusion management, correction of coagulopathy, and difficult IV access. Additionally, anesthesiologists are accustomed to directing a team of personnel in the management of operative patients. This skill set can be utilized for the direction of modular teams during a disaster.

These concepts are vitally important for anesthesiologists to understand because it is likely that during a disaster, anesthesiologists, as perioperative physicians, will be called upon to care for patients at the prehospital disaster site, ED, decontamination area, triage, OR, or in an expanded ICU setting. ICUs will need to augment their capacity during an emergency and ensure supplies and personnel are available to not only care for existing patients within the ICU but also for the influx of injured patients. In these scenarios, patients who can be sent to the floors must be transferred to make room for those who are critically ill. Essential equipment, such as ventilators, infusion pumps, etc, must be located quickly and efficiently and be ready for use.⁴

In France, where anesthesiologists are key members of SAMU, they have been involved in the primary management of mass casualty victims for the past 30 years.⁷ One of the goals of SAMU is to bring the providers to the patients. Indeed, the involvement of anesthesiologists and other physicians in resuscitation at the prehospital stage has been found to reduce 30-day mortality.⁸

Location-Specific Management

Given the diverse training that anesthesiologists and intensivists undergo, they are uniquely poised to function in a variety of settings. Understanding their roles in these different settings is vital to the mission of the disaster plan. For instance, spending an inordinate amount of time at the disaster site in attempting to perform secondary trauma surveys and identifying non–life-threatening injuries is detrimental to the care of casualties as a whole. A brief description of differing roles, based on location of care, is provided below.

Prehospital Care

As noted above, anesthesiologists have played a key role in French prehospital emergency response to MCEs for decades.⁷ These events often involve a myriad of mechanisms for traumatic injury from blunt and penetrating trauma to chemical, biological, and radiological exposures. An anesthesiologist’s or intensivist’s role in the prehospital phase of treatment would be to identify patients with significant injuries to the head or chest as well as the abdomen or limbs that can result in shock. The final common pathway in many traumatic and toxic states is shock leading to decreased delivery of oxygen, which leads to tissue hypoxia.⁷ Pulmonary edema, contusion, and an intense inflammatory response may occur after blast injuries. These lung injuries may precipitate acute respiratory distress syndrome (ARDS) and require prolonged ventilatory support. The anesthesiologist and intensivist are intimately familiar with these disease processes. In France, SAMU is medically controlled, which allows for physician involvement in the field, thereby bringing the advanced care available in the ICU or ED to the patient at the disaster site.⁷

Triage

In many ways, anesthesiologists are ideally suited for triage. In a mass casualty situation, the ED will quickly become overwhelmed and the PACU or step-down unit may be called upon to function as a triage site. The goal of triage is to sort patients into groups according to severity of injury: immediate care, delayed care, first aid, and expectant. Patients with injuries that are likely incompatible with life, such as massive intracranial trauma, will get an expectant designation. Resources such as imaging, operative care, and critical care are directed toward patients who are likely to survive. Expectant patients will be kept comfortable with adequate pain management. Triage decisions, such as whether to take a patient to the OR, are made by the triage officer who should make the decision based on clinical factors, such as refractory hypotension in hemorrhagic shock.^2,4 Anesthesiologists and anesthesiology intensivists, as perioperative physicians, are well versed in identifying derangements in physiology and determining which patients would benefit from a trip to the OR versus continued resuscitation in the ICU.

Expanded ICU

With the ICU at capacity during an MCE, the PACU, ED, and other areas of the hospital may serve as makeshift ICUs. The hospital disaster response plan must account for any additional equipment needed, such as extra ventilators, infusion pumps, and chest tube equipment, and an adequate drug supply. If these logistical contingency plans are not in place before an MCE, the hospital will be unable to manage the increased volume of casualties. In an expanded ICU setting, the intensivists will lead overall management of the ICU; however, numerous providers will need to step in to assist, including anesthesiologists, hospitalists, pediatricians, nurse practitioners, physician assistants, and other providers.⁴

As an anesthesiologist and a perioperative physician, understanding the principles of critical care management, including restoration and continuation of end-organ oxygen delivery, reversing shock states, advanced airway management, correction of severe metabolic disturbances, and the treatment of common disease processes—such as diabetic ketoacidosis, rhabdomyolysis, and bacterial infections—is essential.

Chemical Agent Exposures

Decontamination

One of the most important aspects of treating victims of chemical exposure is to remember that decontamination is essential. Neglecting decontamination procedures will lead to contamination of the hospital as well as the staff. However, to plan for decontamination, the use of a chemical or biological agent must first be recognized by medical personnel. Often, clues to chemical or biological agent exposure can prompt the physician to investigate further (Table 2).^4,9-11

Removing exposed patients from the disaster area, safely placing all clothing into labeled bags, and then decontaminating each exposed victim with soap and water is important before entrance into the health care facility. If patients are also injured, or in cardiopulmonary failure, they will require specially trained teams who can safely address their immediate medical issues and perform decontamination procedures.⁴ If necessary, parking lots outside the hospital can be converted into a decontamination facility. Makeshift tents can be erected to preserve modesty, and tarps can be placed on the ground so that all the effluent can be collected to avoid contaminating the environment. Each patient coming through decontamination will need to have their clothes removed, undergo soap and water decontamination, and then be admitted to the ED or ICU.⁴

Medical personnel must ensure they are wearing proper personal protective equipment. Occupational Safety and Health Administration Level C gear (full face mask, hood, canister filtration device, chemical barrier suit, gloves, and boots) should provide adequate protection. Once decontamination is complete, patients will enter the ED and be triaged to either the ICU or an observation unit, depending on severity of illness.⁴

Nerve Agents

Nerve agents—tabun (GA [initials are the military’s acronym]), sarin (GB), methylphosphonothioic acid (VX), and soman (GD)—were first developed in Germany for military use, and chemically resemble organophosphate pesticides. Their mechanism of action is secondary to potent inhibition of the enzyme acetylcholinesterase (AChE). AChE degrades acetylcholine (ACh). In the absence of functional AChE, ACh accumulates at the synapse resulting in excessive stimulation of cholinergic neurons and cholinergic crisis. Nerve agents inactivate AChE by alkyl phosphorylation of a serine hydroxyl group, allowing ACh to build up at nicotinic, muscarinic, and central nervous synapses.¹⁰ Phosphorylated AChE is incredibly stable, and its stability is enhanced when the enzyme loses an alkyl side chain. This chemical process is known as aging. This is an irreversible process, and the only way to regenerate AChE is to produce more of the enzyme.¹⁰ Nerve agents also inhibit erythrocyte cholinesterase and plasma esterase. Therefore, measurement of serum red blood cell cholinesterase can confirm nerve agent exposure .¹⁰However, diagnosis and treatment should not be delayed for confirmatory laboratory testing. This is an essential teaching point.

Properties of Nerve Agents

Most nerve agents are liquids at room temperature and highly lipid soluble, facilitating entry through the skin and into the central nervous system. Sarin is the most volatile agent, allowing it to be rapidly inhaled.¹⁰

Presentation

Depending on the route and time since exposure, patients can present in cholinergic crisis, with symptoms characteristic of a cholinergic toxidrome. Overstimulation of muscarinic receptors leads to lacrimation, salivation, bronchorrhea, bronchospasm, miosis, rhinorrhea, and gastrointestinal hyperstimulation (vomiting and diarrhea), whereas overstimulation of nicotinic receptors results in fasciculations, flaccid paralysis, tachycardia, and hypertension.⁹ Seizures are also possible.

The DUMBELS (diarrhea, urination, miosis, bronchorrhea, bronchospasm, emesis, lacrimation, salivation) mnemonic is a helpful aid in cholinergic crisis symptomology. Often, miosis is the first physical exam sign seen. In fact, during the Tokyo subway sarin attack, miosis was the most prevalent finding on exposure victims.¹⁰ Chest tightness is an early finding, which progresses quickly as levels of the agent build up in the circulation.⁴ Tachycardia rather than bradycardia often predominates due to increased sympathetic stimulation of nicotinic receptors. The most common cause of death from nerve agent exposure is respiratory failure secondary to paralysis of the muscles of respiration and intense bronchorrhea.¹⁰

Management

As discussed previously, evacuation of patients from the disaster site and decontamination are of paramount importance. Initial management should focus on the ABCs of resuscitation—airway, breathing, and circulation—as respiratory failure is the leading cause of death in this group. It is key to remember when securing the airway that nondepolarizing and depolarizing neuromuscular blocking drugs (succinylcholine) have prolonged action in this group.

Endotracheal intubation and mechanical ventilation are the mainstays of treatment for respiratory failure. Due to muscarinic receptor overstimulation leading to bronchoconstriction and bronchorrhea, airway pressures may be markedly elevated, necessitating high driving pressures.⁹

With regard to antidote administration, it is often helpful to remember the following⁹:

• Muscarinic receptor overstimulation (diarrhea, urination, bronchorrhea, bronchospasm, emesis, lacrimation, salivation) is treated with atropine.
• Nicotinic receptor overstimulation (muscle fatigue, weakness, cramps, fasciculations) is treated with pralidoxime chloride (2-PAM).
• Central nervous system effects (seizures) are treated with benzodiazepines (diazepam, midazolam, or lorazepam).
• Respiratory failure is treated with supportive mechanical ventilation.

Of key importance is to realize that atropine, while treating many of the muscarinic effects of nerve agents, does not regenerate ACh. 2-PAM, when administered before aging of the nerve agent, binds to the agent and breaks the alkyl phosphate–cholinesterase bond, thereby allowing AChE activity to increase. However, once aging has occurred, it can take several days to weeks for ACh to regenerate.⁴ 2-PAM is rapidly excreted in urine; therefore, it is essential to redo or provide continuous infusion after the initial dose.¹⁰ Although diazepam is the most commonly used benzodiazepine for anticonvulsant activity in the field, in the ICU setting, midazolam and lorazepam may be more effective. Other anticonvulsants such as phenytoin, carbamazepine, and valproic acid do not have activity against seizures caused by nerve agents.⁴

Vesicants

Much like patients with burn injuries, victims of exposure to vesicants—mustard gas (HD), lewisite (L), and phosgene oxime (CX)—require airway protection and marked fluid resuscitation. In more recent memory, mustard gas was used during the Iran–Iraq War. The hallmark of vesicants is their mechanism of action: They carry a highly reactive sulfonium group that binds to many different substances in humans and animals, including nucleic acids and proteins. The sulfonium group alkylates biological compounds, resulting in disruption of cell division and DNA synthesis.⁴

Vesicants affect the eyes, mucous surfaces, lungs, skin, and erythrocyte-generating regions, such as bone marrow. Eye symptoms such as photophobia, tears, and irritation can occur as quickly as 30 minutes after exposure. However, symptoms due to vesicant exposure to the skin can be delayed for many hours (6-12 hours), which can result in lack of decontamination, as the patient or health care provider does not realize exposure has occurred.⁴

Damage caused by vesicants is heightened by moisture and warm temperatures. Fluid-filled blisters and desquamation of skin occur in areas covered by clothing, with eventual development of ulcers. Vesicants irritate the mucosal surfaces of the mouth, nasal passages, sinuses, and bronchi. In severe cases, pneumonia and pseudomembrane formation can lead to airway obstruction.⁴

Treatment is essentially supportive. Patients require the level of critical care management that a burn center usually provides. Key measures include⁴:

• removal of contaminated clothing;
• volume resuscitation due to insensible loss;
• surveillance and protection of the airway, if necessary;
• topical antibiotic coverage for risk for infection due to loss of skin integrity with desquamation; and
• administration of intramuscular dimercaprol at 3 mg/kg for systemic lewisite poisoning, which forms a water-soluble compound that is eliminated in the urine.

Cyanides and Pulmonary Agents

Examples of pulmonary agents include phosgene and chlorine gas. These agents mainly cause an intense inflammatory response in the airway and lungs that can lead to ARDS. Treatment is mainly supportive and includes endotracheal intubation and mechanical ventilation. Cyanides such as hydrogen cyanide (AC), cyanogen chloride (CK), and cyanide salts are quickly taken up by systemic circulation. These agents inhibit mitochondrial cytochrome oxidase, which is essential for aerobic respiration. Their action on mitochondrial cytochrome oxidases results in tissue hypoxia and lactic acidosis. In this way, blood oxygen levels are normal, but oxygen cannot be used by the tissues.⁹ Although the diagnosis is mainly clinical, a very high venous partial pressure of oxygen can increase suspicion of cyanide toxicity.

Symptoms of cyanide poisoning vary between nausea, headache, dizziness, and anxiety from small doses to seizures, cardiac arrest, tachypnea, and death within a few minutes from large doses. Route of entry is usually by inhalation, but cyanides can also be absorbed by the skin. Whether the route is dermal or inhalational, absorption into systemic circulation is rapid.^9,10

Treatment includes 100% oxygen; mechanical ventilation, if necessary; and administration of inhaled amyl nitrate, IV sodium nitrite, and sodium thiosulfate. Amyl nitrate and sodium nitrite oxidize ferrous iron on hemoglobin to ferric iron, forming methemoglobin. Cyanide has a higher affinity for methemoglobin over hemoglobin, leading to sequestration of cyanide by methemoglobin. Sodium thiosulfate combines with free cyanide, forming thiocyanate, which is excreted in the urine. Hydroxocobalamin also binds free cyanide, forming cyanocobalamin, which is also excreted in the urine.¹⁰

Radiological Exposure

With the increase in worldwide terrorist activity, the possibility of a dirty bomb (conventional explosives mixed with radioactive material) detonation on US soil is highly concerning. It is also concerning that many hospitals lack the equipment to immediately detect radiation exposure. Dirty bomb explosions generally result in more conventional blast injuries than high-dose radiation exposure. The ability to diagnose and treat radiation poisoning, however, is essential.⁴

Types of ionizing radiation include⁴:

• alpha particles
• beta particles
• gamma particles
• neutrons

Alpha particles, externally, do not pose a major threat to humans. However, if alpha-emitting particles are ingested, the chromosomal damage can be devastating. Beta particles, on the other hand, can travel a few centimeters through air and short distances through tissue. If exposed to beta particles for a long period of time, radiation burns can occur on the skin. By far, the most damaging types of radiation are gamma rays and neutrons. The larger mass of neutrons makes them highly damaging to tissue. Neutrons are only emitted during detonation of a thermonuclear device or reactor mishap.⁴

During a mass casualty incident involving radioactive materials, it is vital to distinguish between irradiated patients and contaminated patients. Irradiated patients have been exposed to ionizing radiation but are not themselves radioactive. Contaminated patients have come into physical contact with radioisotopes and emit radiation.4 Proper decontamination of contaminated patients is essential before entering the health care facility. Radioactively contaminated patients pose a high risk to health care workers and anyone with whom they come into contact. Clothes, urine, feces, bodily fluids, and wastewater from skin decontamination must all be collected safely and not allowed to contaminate the environment.

All patients must pass through decontamination without exception. Radiation counts should be conducted before decontamination to estimate the dose patients have received and after decontamination to gauge the success of decontamination. A Geiger-Müller counter is sufficient to estimate the exposure dosage from beta and gamma radiation, as well as from x-rays.⁴

Estimating radiation dose is critical because after decontamination, triage, and stabilization, patients who have received a significant dose of ionizing radiation must be assessed for acute radiation syndrome. These patients must be secondarily triaged and then treated, depending on the type of radiation and dose they received. A patient’s exposure dose depends on⁴:

• the distance from the radiation source (doubling the distance decreases irradiation by a factor of 4);
• any shielding between the patient and the source; and
• length of exposure.

Estimates of exposure dose can be determined by use of the Armed Forces Radiobiology Research Institute’s Biodosimetry Assessment Tool. The following steps should be followed in the management of exposure to ionizing radiation:

• Evacuate the victim from the source of ionizing radiation—the longer the exposure, the higher the dose.
• Decontamination is vital. All clothing must be removed and carefully isolated, and the skin and hair must be washed with soap and water, taking care to capture the runoff to prevent contaminating the water supply. This process removes greater than 95% radiation contamination from a victim’s skin.
• Treat life-threatening injuries first, then decontaminate, and then attempt to determine radiation dose to secondarily triage for appropriate treatment.
• If the patient was exposed to a nuclear explosion or reactor mishap, administer potassium iodide at 1 dose daily for 3 days.
• Patients exposed to 6 to 8 Gy may still benefit from treatment.
• Patients exposed to greater than 10 Gy are unlikely to survive.
• Neutropenic patients will require antibiotic, antiviral, and antifungal treatment.

ICU management includes estimation of radiation dose, HLA typing in the event that bone marrow transplantation is required, volume resuscitation, empirical antibiotic therapy, antidiarrheal agents, antiemetic agents, airway management, management of electrolyte derangements, blood and platelet transfusions with leukoreduced and irradiated products if the patient has a severely depressed hematopoietic system, and bone marrow stimulation with recombinant granulocyte colony-stimulating factor.^4,12

Infectious Diseases

The CDC has protocols in place for notification of local and state public health departments in the event of a biological attack. Release of biological agents such as viruses, toxins, and bacteria is difficult to detect because they can be easily disseminated on a large population in a multitude of ways—through the air, water, or food supply, or via explosives.

Events that can alert health officials to a possible bioterrorism incident are:

• a rapid rise in numbers of sick individuals presenting with similar symptoms in a short period of time;
• a disease that is usually seen in a different season emerging uncharacteristically;
• many patients from one area with high numbers of fatalities; and
• patients presenting with diseases that are known to be used as weapons, such as anthrax and plague.

It is important for hospitals and physicians to be knowledgeable about the CDC’s Bioterrorism Readiness Plan, which can guide medical personnel in the development of a response plan. Additionally, anesthesiologists and intensivists should familiarize themselves with agents likely to be used as biological weapons, as well as their symptoms and treatments.9 Familiarization with likely agents of biological warfare or bioterrorism should focus on organisms and toxins that the CDC believes would inflict the most harm to our population.

CDC Category A agents include those with a great potential for inflicting casualties due to the ability to disseminate them over a large area. Category A agents include4:

• anthrax
• smallpox
• plague
• tularemia
• viral hemorrhagic fevers
• botulism

CDC Category B agents include those that are relatively easy to spread over a large area but have lower mortality rates than the agents in Category A. Category B agents include⁴:

• Brucellosis
• Viral encephalitis
• Epsilon toxin of Clostridium perfringens
• Salmonella
• Escherichia coli
• Shigella
• Burkholderia mallei
• Melioidosis
• Psittacosis
• Coxiella burnetii
• Ricin toxin
• Staphylococcal enterotoxin B
• Typhus fever

Reviewing these infectious agents and toxins and their treatments is fundamental to disaster preparedness.

Conclusion

In this age of the blurring of lines between medical specialties, greater demands being placed on the medical system, and more devastating injuries caused by mass casualty incidents, anesthesiologists and anesthesia critical care physicians—with their vast experience in airway management, intravascular access, management of shock states, and the coagulopathy of trauma—must push for greater involvement and assume greater roles within hospital and community disaster preparedness plans.

It is also critical for anesthesiology residents to be trained in basic disaster management, advanced trauma life support, and the care of patients subjected to blasts, chemical, biological, and radiological disasters. An anesthesiologist can no longer merely be thought of as the doctor who “puts you to sleep.” As we have done many times during the long and honorable history of this profession, we must be bold in our vision and set the standards for medicine by embracing and growing into our role as the perioperative physician—even when working in extremis during an MCE.

References

1. Hirsch M, Carli P, Nizard R, et al. The medical response to multisite terrorist attacks in Paris. Lancet. 2015;386(10012):2535-2538.
2. Kuza C, McIsaac J. Roles of the anesthesiologist during mass casualty events. ASA Monitor. 2017;81(4):14-17.
3. Regional Response Coordination Centers. FEMA fact sheet. July 2015. www.fema.gov/?media-library-data/ ?1440617086850-f6489d2de59dddeba8bebc9b4d419009/?RRCC_ July_2015_508.pdf. Accessed September 6, 2018.
4. Geiling JA, ed. Fundamental Disaster Management. 3rd ed. Mount Prospect, IL: Society of Critical Care Medicine; 2009.
5. Waeckerle JF. Disaster planning and response. N Engl J Med. 1991;324(12):815-821.
6. Murray MJ. Communicating during a disaster. Anesth Analg. 2010;110(3):657-658.
7. Baker DJ, Telion C, Carli P. Multiple casualty incidents: the prehospital role of the anesthesiologist in Europe. Anesthesiol Clin. 2007;25(1):179-188.
8. Yeguiayan JM, Garrigue D, Binquet C, et al. Medical pre-hospital management reduces mortality in severe blunt trauma: a prospective epidemiological study. Crit Care. 2011;15(1):R34.
9. Vincent JL, Abraham E, Moore FA, et al. Textbook of Critical Care. 7th ed. Philadelphia, PA: Elsevier; 2011.
10. Geoghegan J, Tong JL. Chemical warfare agents. Contin Educ Anaesth Crit Care Pain. 2006;6(6):230-234.
11. CBRNE – nerve agents, G-series – tabun, sarin, soman medication: anticholinergics, oximes, benzodiazepines, mydriatic-cycloplegics, cholinesterase inhibitors. Background, pathophysiology, etiology. https://emedicine.medscape.com/?article/?831648-medication#. Published May 2, 2017. Accessed September 6, 2018.
12. Knechtges PL. An Evaluation of Blood Cholinesterase Testing Methods for Military Health Surveillance. Fort Detrick, MD: US Army Center for Environmental Health Research (USACEHR); 2008. USACEHR Technical Report 0801. www.researchgate.net/?publication/?235133899_ An_Evaluation_of_ Blood_ Cholinesterase_ Testing_ Methods_for_ Military_Health. Accessed September 6, 2018.